To assess the quality of an analog/digital converter (AD converter), the values for SNR (signal to noise ratio), SINAD (signal plus noise plus distortion to noise plus distortion ratio), SNDR (signal to noise plus distortion ratio), and THD (total dynamic distortion) are usually ascertained. As the standard IEEE Std 1241-2000 describes, an AD converter is preferably analyzed by applying an analog signal and subsequently subjecting the test response to Fast Fourier Transformation (FFT). This involves calculating all the spectral components of the test response of the AD converter and from these the values for SNR, SINAD, SNDR and THD. FFT analysis is very computation intensive and results in long test times.